Carbon Commentary newsletter

1, Vehicle to Grid. Despite the obvious commercial case for V2G, progress has been slow. However we’re beginning to see signs that automakers understand the logic of allowing their customers to trade electricity (and thus help match supply and demand on the grid). Hyundai announced two experiments in the Netherlands and on an island in its home country of Korea that faces grid stability issues. Two of its cars - the Kia EV9 and the Ioniq 9 – will be able to charge and discharge electricity. Hyundai also said it would extend experimentation to the US in the near future. In Germany, BMW recently indicated it would equip one of its models, the iX3, with V2G capability and in the last few weeks, the German regulator removed the grid charges on EV batteries exporting power. There are substantial technical challenges making the EV fleet capable of V2G but the increasing need for electricity storage as renewables grow makes the case for implementation stronger by the day. In the US, Clean Technica reported that the Cadillac brand has now also embraced ‘vehicle to home’ for its new vehicles.

2, Grid investment. Electricity prices in many developed countries are increasing. One important cause is the payments for upgrades to the transmission and local distribution systems. These improvements are driven by the need to integrate renewables and to ensure better connections with international markets. One recent analysis (https://www.electricitybills.uk/2030) of likely changes in UK retail prices shows that by 2030 transmission and distribution costs alone will exceed the price of the electricity. Wholesale costs of UK electricity will fall to less than 25% of the retail price, down from almost 34% in 2025. One unrecognised implication is that consumers face stronger and stronger incentives to reduce electricity use, or to generate power themselves. This will hold down total grid demand, implying that rising transmission and distribution costs will need to be spread over smaller volumes, further increasing the price per kWh.

3, Unusual demand response. The Nostromo Ice Brick, a way of storing cooling capacity, became a formal part of the Californian demand response system. When electricity is available, the Ice Brick creates freezes water which can then be used to provide, for example, air conditioning at a later time. Nostromo also announced a product aimed at data centres, enabling cooling capacity to be stored, reducing the need for electricity at busy times. The company says that cooling needs often account for ‘10-30%’ of peak electricity use at data centres.

4, Methanol bunkering for ships. There are now over 450 ships with the capacity to fuel with methanol. However these ‘dual fuel’ vessels still travel almost exclusively using heavy fuel oil (HFO) because of a shortage of sites that bunker the methanol alternative. Singapore, one of the busiest ports in the world, reports that it has just completed the first full refuelling of a dual fuel ship by transferring methanol from a bunker ship in the port. Other suppliers are adding bunker ships over the next few weeks. The alternative fuel made using current techniques probably has a carbon cost at least as great as HFO but green methanol sources are likely to offer substantial savings in CO2, as well as other pollutants. China has invested heavily in green methanol refineries even though market prices are still roughly three times the price of HFO.

5, Degradable plastics. We know that plastics from biological sources can be engineered to break down quickly compared to conventional variants. Researchers at Rutgers University in the US have now shown that it is possible to manufacture plastics from oil that will disintegrate at a predetermined time after being used. So takeout food packaging could be given a very short life while durable plastics could be made to last decades before breaking down. Degradability will reduce the litter problem on land and at sea but doesn’t reduce the carbon cost of making plastics. Nevertheless I suspect that this research will be enthusiastically taken up by the oil industry because it will ensure more demand for petrochemical refineries whereas full recycling will cut the demand for new plastics.

6, Battery swapping for heavy trucks. Electric heavy trucks made up 22% of sales in China in the first half of 2025 and one research report estimates that battery powered units may represent as much as 60% of 2026 sales. H1 2025 sales tripled compared to the same period in 2024 with suppliers also exporting increasing numbers of vehicles. Rapid charging networks are developing fast on the main freight routes. CATL also will have installed about 300 battery swapping stations for heavy freight vehicles by the end of the year. It has introduced a standard battery pack for trucks enabling (it says) a 150 second complete battery swap.

7, Geothermal heat storage. Depleted oil fields may be good locations for seasonal storage of heat, perhaps generated by excess electricity production in summer. Germany gave permission for drilling a trial well for what is called a ‘geothermal battery’ on the campus of the Karlsruhe Institute of Technology. The drilling will go down to about 1,400 metres below the surface. If the trial works, water heated to 140 degrees will be injected into a reservoir typically at around 70 degrees. (Karlsruhe lies in the Upper Rhine Graben, an area in which underground temperatures are high, making extracting heat using conventional geothermal plants also possible). One estimate is that the Upper Rhine Graben could be used to store up to 10 TWh of heat a year in depleted oil fields.

8, Finland synthetic fuels hub. The northern Finnish port of Oulu seems likely to become the first synthetic fuels hub in the Baltic Region and possibly in Europe. Low electricity prices have pulled e-fuels developers into the area and the German producer Hy2Gen joined five other companies planning projects in the area with a proposal for a 200 MW development. The likely growth of the hub is partly due to the availability of electricity and good port access but also to the hydrogen research at the city’s university.

9, Australian domestic rooftop solar. About one third of Australian homes now have solar on the roof, generating about 8% of total national need for electricity. The Australian Bureau of Statistics estimated that this saved Australian households about US$ 2.2bn, equivalent to over US$500 for each home with solar. It also guessed that about half of all rooftop solar power is used in the home and about half is exported. As batteries fall in price, more will be consumed by the household.

10, Tidal energy. EMEC, the centre for research into marine energies, announced the successful completion of a trial that married tidal generation, hydrogen manufacture and battery storage. Based on Orkney, off the northern tip of mainland Scotland, EMEC claims that this project is the first demonstration that the three technologies can work together and thus provide reliable supplies of electricity even though tidal generation varies during the day. The experiment used the Orbital Marine Power tidal turbine, a vanadium flow battery (not a typical quick discharge lithium ion battery) and a 670 kW electrolyser from ITM Power. EMEC said the work had demonstrated that what it calls its 3 in 1 solution can help remote areas integrate variable renewables. The next part of the experiment will be to explore whether the hydrogen can be used to make synthetic fuels.